Geothermal energy is the heat produced by the molten core of the Earth beneath the surface of the planet. The decay of radioactive materials such as uranium and potassium produces this heat on a continuous basis.
Within the first 33,000 feet of the Earth’s surface, heat is produced that generates 50,000 times more energy than all of the world’s oil and natural gas combined. That appears to be a compelling argument in favor of attempting to harness the power of geothermal energy.
Tectonic plate boundaries and places where the crust is thin have the highest underground temperatures, and you don’t have to travel as far to get to the heat that’s being generated by the plates.
Because geothermal energy has the potential to achieve greater than 400 percent efficiency while emitting virtually no emissions, it should come as no surprise that it is considered one of the most efficient, cost-effective, and environmentally friendly sources of electricity.
Geothermal energy is a reliable, inexhaustible, and environmentally friendly source of energy. The advantages of geothermal energy will be discussed in detail in this article.
1. Environmentally Friendly
For every kilowatt-hour of electricity produced, geothermal power plants emit 0.1 to 0.2 pounds of carbon dioxide. Geothermal energy appears to be a very good choice for energy production when compared to coal plants, which emit between 1.4 and 3.6 pounds of carbon dioxide for every kilowatt-hour of electricity produced.
When geothermal heat pumps extract hot water from the ground, it is common for the water to contain high concentrations of sulfur, salt, and other minerals. However, because the vast majority of geothermal plants are equipped with closed loop systems, in which the water extracted is pumped back into the geothermal reservoir, there is no pollution of the water supply.
Geothermal power plants emit no nitrogen oxides, very little sulfur oxide, and very small amounts of carbon dioxide, all of which are harmful to the environment. This group of gases is not emitted during production due to the lack of combustion, but they are naturally occurring constituents of all geothermal reservoirs.
To address the extremely low levels of carbon dioxide produced by geothermal energy, one possible solution is to use the carbon dioxide as a growth stimulant in geothermally heated greenhouses.
Geothermal energy also has the smallest land-use footprint per kilowatt-hour of any energy-generation technology currently available, making it the most environmentally friendly option. For every megawatt of energy produced, a geothermal field may require 1-8 acres of land, compared to 5-10 acres for nuclear energy and 19 acres for coal.
By utilizing their 300 MW geothermal power plant, the state of Nevada has been able to save 4.5 million barrels of oil and avoid 2.25 million tons of carbon dioxide emissions per year, according to the state.
2. High Efficiency and Low Maintenance
Geothermal energy is widely regarded as the most energy-efficient and cost-effective energy system available, with a geothermal heat pump being four to five times more efficient than a gas furnace, according to industry experts.
The coefficient of performance, or COP for short, is used to rate the efficiency of a system. It is, in essence, a method of determining how much energy is produced by a system in comparison to how much energy it consumes.
Geothermal heat pumps have a coefficient of performance (COP) of 3-4.5, which means that for every unit of electricity consumed, 3 to 4.5 units of heat are produced. Therefore, geothermal heat pumps have a potential efficiency of more than 400 percent, while a fossil fuel furnace only has a potential efficiency of approximately 78-90 percent.
The fact that the energy is being harnessed rather than captured through the combustion of fossil fuels enables it to operate at a 400 percent efficiency level.
A geothermal plant’s operating and maintenance costs range from $0.01 to $0.03 per kWh, according to the Department of Energy’s Office of Energy Efficiency and Renewable Energy. It is possible to consider a home system to be virtually maintenance free.
The buried loop that transports the water is expected to last for at least 50 years, and the other half of the system, which includes the fan, pump, and compressor, is expected to last for at least 20 years because it is housed indoors and protected from the elements.
3. Cost Effective and Reliable
It takes an average of 22 years for a geothermal heating system to pay for itself, with costs being recouped in three to seven years. Once the costs have been recovered, the average household can expect to save anywhere between 30 percent and 70 percent on their energy bills.
The cheapest source of energy to generate one million BTUs was geothermal energy. Gas is $15.48 per million BTUs, propane is $29.73 per million BTUs, and fuel is the most expensive at $30.21 per million BTUs, whereas geothermal heating pumps cost only $6.70.
Geothermal power plants have an average availability of 90 percent or higher, whereas coal power plants have an average availability of only 75 percent. This means that geothermal power plants are available 90 percent of the time, with the majority of them operating at around 98 percent.
Geothermal power plants can operate 24 hours a day, seven days a week, regardless of weather patterns or environmental conditions, and they are not subject to the voltage swings and unpredictability that are common with nonrenewable sources of energy.
Geothermal plants are scalable, which means that a small plant for applications within a community can be built economically, and large-scale facilities on the order of several megawatts (MW) can also be built economically.
4. Supports Local Economic Development
Renewable energy technologies, in contrast to fossil fuel technologies, are significantly more labor intensive, resulting in the creation of significantly more jobs on average for each production facility generated.
Several geothermal resources that can be used for energy production are located in rural areas, many of which are experiencing economic depression and unemployment at the present time. Geothermal development creates jobs and generates tax revenues that have a significant positive impact on the economy.
Careers in science and technology, management and administrative support, construction, manufacturing, and operations are just a few of the many different types of jobs that geothermal energy production has the potential to generate.
A total of 225 part-time jobs and 425 full-time jobs were created by the Geysers Geothermal Complex in California. Approximately 1.7 jobs are created for every megawatt of installed geothermal power generation capacity in power plant maintenance and operations, as well as in other areas of geothermal development, such as research, legal and government regulators, as well as in the field of al development.
Geothermal power plants also generate temporary employment opportunities in the manufacturing and construction industries. With 3.1 construction jobs per megawatt installed and 3.3 manufacturing jobs per megawatt installed, renewable energy is a good investment.
Following the passage of the Geothermal Steam Act Amendments in 2005, which required that 25 percent of revenues generated from geothermal leasing and production be allocated to state and local governments, the Geothermal Energy Association states that Nevada received $7.5 million in 2008, and the state allocated all of that money to the support of public schools.
California reported revenues of $4 million in 2011, with a total of $188 million in revenue since 1972, according to the state’s financial reports. It is estimated that geothermal energy generated $15 million in royalties and rents from federal land use in the United States alone in 2013.
Tourists can also be attracted to geothermal plants. The Blue Lagoon, a geothermal spa connected to the Svartsengi power plant, is Iceland’s most popular tourist destination, having welcomed more than 75,000 visitors since it first opened its doors in 2001.
While geothermal energy produces fewer emissions than coal and oil plants, the environmental impacts of geothermal energy production are vastly less severe than those of current energy production methods. Geothermal energy is extremely practical and feasible in terms of economics and practicality.
For example, geothermal energy has the potential to completely replace oil and natural gas-based heating and cooling systems in many areas, resulting in lower annual costs, lower CO2 emissions, and lower emissions of other harmful pollutants.
In order to improve their ability to control their economic future and national security, countries should increase the availability of geothermal energy and other natural resources, while at the same time conserving oil and natural gas resources for higher value uses such as liquid transportation fuels, chemical feedstock, and pharmaceutical production.
Development is being stymied in the United States not because of economic obstacles, but rather because of political, structural, and policy obstacles. The public as a whole must take an active role in the production of clean, safe, and renewable energy, and geothermal energy is being ignored and underestimated at the present time.
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